1221012329 has 4 divisors (see below), whose sum is σ = 1224701520. Its totient is φ = 1217323140.

The previous prime is 1221012319. The next prime is 1221012337. The reversal of 1221012329 is 9232101221.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1221012329 - 2⁴ = 1221012313 is a prime.

It is a super-2 number, since 2×1221012329² = 2981742215140008482, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221012319) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1844099 + ... + 1844760.

It is an arithmetic number, because the mean of its divisors is an integer number (306175380).

Almost surely, 2^1221012329 is an apocalyptic number.

It is an amenable number.

1221012329 is a deficient number, since it is larger than the sum of its proper divisors (3689191).

1221012329 is an equidigital number, since it uses as much as digits as its factorization.

1221012329 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3689190.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 1221012329 is about 34942.9868357014. The cubic root of 1221012329 is about 1068.8251958811.

The spelling of 1221012329 in words is "one billion, two hundred twenty-one million, twelve thousand, three hundred twenty-nine".